Self-Diagnosis Table - Mitsubishi Heavy Industries SRK10CNV Technical Manual

(5) Self-diagnosis table

Indoor unit display panel
RUN TIMER
light light
1-time
ON
flash
2-time
ON
flash
6-time
ON
flash
Keeps 1-time
flashing flash
Keeps 2-time
flashing flash
Keeps 4-time
flashing flash
2-time
ON
flash
5-time
ON
flash
6-time
ON
flash
Description
Cause
of trouble
• Broken heat exchanger sensor
Heat exchanger 1 wire, poor connector
sensor 1 error connection
• Indoor PCB is faulty
• Broken room temperature
Room
sensor wire, poor connector
temperature
connection
sensor error
• Indoor PCB is faulty
Indoor fan • Defective fan motor, poor
motor error connector connection
• Broken outdoor air temp.
Outdoor air
sensor wire, poor connector
temperature
connection
sensor error
• Outdoor main PCB is faulty
• Broken heat exchanger sensor
Outdoor heat
wire, poor connector
exchanger
connection
sensor error
• Outdoor main PCB is faulty
• Broken discharge pipe sensor
Discharge pipe wire, poor connector
sensor error connection
• Outdoor main PCB is faulty
Trouble of • Broken compressor wire
outdoor unit • Compressor blockage
• Gas shortage, defective
Over heat of
discharge pipe sensor, service
compressor
valve is closed
• Defective power supply,
Error of signal
Broken signal wire, defective
transmission
indoor/outdoor sub PCB
Display (flashing) condition
When a heat exchanger sensor 1 wire disconnection is detected while
operation is stopped. (If a temperature of –28ºC or lower is detected for
15 seconds, it is judged that the wire is disconnected.)
(Not displayed during operation.)
When a room temperature sensor wire disconnection is detected while
operation is stopped. (If a temperature of –45ºC or lower is detected for
15 seconds, it is judged that the wire is disconnected.)
(Not displayed during operation.)
When conditions for turning the indoor unit's fan motor on exist during air
conditioner operation, an indoor unit fan motor speed of 300 rpm or lower is
measured for 30 seconds or longer. (The air conditioner stops.)
–55ºC or lower is detected for 5 seconds continuously 3 times within
40 minutes after initial detection of this anomalous temperature.
Or –55ºC or higher is detected for within 20 seconds after power ON.
(The compressor is stopped.)
–55ºC or lower is detected for 5 seconds continuously 3 times within
40 minutes after initial detection of this anomalous temperature.
Or –55ºC or higher is detected for within 20 seconds after power ON.
(The compressor is stopped.)
–25ºC or lower is detected for 5 seconds continuously 3 times within 40
minutes after initial detection of this anomalous temperature.
(The compressor is stopped.)
When there is an emer gency stop caused by trouble in the outdoor unit,
or the input current value is found to be lower than the set value.
(The air conditioner stops.)
When the value of the discharge pipe sensor exceeds the set value.
(The air conditioner stops.)
When there is no signal between the indoor PCB and outdoor PCB for
10 seconds or longer (when the power is turned on), or when there is no
signal for 7 minute 35 seconds or longer (during operation)(the
compressor is stopped).

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'09•SRK-DB-087D
'14•SRK-T-153